Scientists have developed a method to turn plastic waste into clean hydrogen using solar power and acid from old car batteries.

The one-pot process transforms hard-to-recycle plastics into valuable industrial chemicals and clean fuel, potentially creating a circular upcycling system that tackles multiple problematic waste streams at once, the researchers say.

Condensation polymers like polyethylene terephthalate (PET, often used for packaging food and drinks), polyurethane (PU, which can be used in foam cushioning, bedding and insulation), and nylon fall into this latter category. A chemical reaction between two different monomer units releases water to form bonds between these fragments, creating a long alternating polymer chain.…